In a new browser tab navigate to Sophia.org by right clicking the link and choosing to open in a new tab
Make sure you're signed into your Google+ account
Click the Sign up button in the upper right corner
Use your newly created Google account to sign-in to sophia.org by clicking the 'g+ sign In' button (seen below). By doing this you will not have to remember another username and password.
In the next window you will use the correct class code from below (copy cut and paste) into the box to join your group (should match the hour of class you're in). Click join.
You should see a window that shows what groups you're in (seen below). The group number should match your class hour.
Your all done. Now click on your group and see what activities that you waiting you.